Abdominal exercise device



FIG. 1 is a top perspective view of an abdominal exercise device showing our new design;

FIG. 2 is a top plan view of the abdominal exercise device;

FIG. 3 is a front elevational view of FIG. 2;

FIG. 4 is a rear elevational view of FIG. 2;

FIG. 5 is a bottom plan view of FIG. 2; and,

FIG. 6 is a left side elevational view of FIG. 2, the right side being a mirror image thereof. 

The ornamental design for an abdominal exercise device, as shown and described. 